Are mixed breeds genetically healthier than pure breeds?

[BCSnob]

In my recent reading of canine genetics articles I came across this gem. For some time know I have thought that for genetic diseases mixed breeds are just as prone to be affected as pure breeds since mixed breeds come from a mix of pure breeds. This article summarizes multi-breed genetic diseases and breed-specific genetic diseases.

Mark

We deal with genetic disease every day in our practice in
pure-bred, cross-bred and mixed-breed dogs. There is
a general misconception that mixed-breed dogs are
inherently free of genetic disease. This may be true for
the rare breed-related disorders, but the common genetic
diseases that are seen across all breeds are seen with the
same frequency in mixed-breed dogs.

**************************************************************

Breed-specific genetic diseases tend not to spill out into
the mixed-breed populations. Exceptions to this, however,
are ancient mutations that occurred before the separation
of breeds. These disease-causing genes mutated
so long ago that the mutation (and its
associated disease) is found in
evolutionary divergent breeds.

************************************************************

The most common hereditary diseases occur across all
pure-bred, mixed breed and designer-bred dogs. These
include cancer, eye disease, epilepsy, hip dysplasia,
hypothyroidism, heart disease, autoimmune disease,
allergies, patellar luxation and elbow dysplasia.

****************************************************************

The production of designer breeds — planned crosses
between two breeds to produce offspring — has become
a growing trend in commercial dog breeding. Puggles,
Yorkipoos, Cavishons and Labradoodles, to name a few, are
all coming into our clinics. Owners believe that these pets
will be genetically healthy because they are cross-bred. As
we treat these patients, we know that this is not the case.

Source: The Clinical Truths about Prue Breeds, Mixed Breeds, and Designer Breeds
Jerold Bell, DVM

[Code2High]

dturm wrote:

CA POPPY wrote:
If I was "placing" Daisy I would call her a Beagle/Lab cross. At least I'd know she'd be adopted. :B

:B We never see Pit crosses coming from rescues around this area. Go figure...

Ziggy is listed as a "lab mix" on her adoption papers. When I got her, I lived in a place where pits were not allowed. I did assure the shelter staff that I'd move before I'd ever give her up, and she's listed as a pit on my insurance now.

Unfortunately, it works both ways. Any dog, short-haired in particular, is subject to being labeled as a "pit mix," even though they frequently bear little resemblance to the breed. Pointers are frequently mis-identified as a lot of them have fairly coarse muzzles. Boxer mixes, mastiffs, labs, you name it. Sometimes there is a blockier look to their head and that's why, sometimes not.

Of course, if the dog has been involved in a bite or a fight incident, that is even more likely to happen. This may doom the dog and also tars actual pits with the brush of whatever that dog did.

There are certain facial features that do tend to show up, such as a particular curve to the jawline, the muscular head that's heart-shaped on top, pronounced stop, big fat blunt snoot (the better to hit...er, kiss... you with... from a sitting position on the floor). Other things are more difficult to describe, such as the eyes, but when I see them the resemblance is impossible to miss. Not to mention heartbreaking, since the ones I see are usually on death row.

Still, getting back to the issue in this thread, they are mostly a pretty healthy lot, other than a tendency to demodex, which seems to respond well to treatment in most cases. You don't hear a lot of pit owners talking about losing a five year old to cancer or DM developing later in life... so there's that. When Zig is old and perfect, I'll have a pretty good shot at having her a good long while.

[dturm]

CA POPPY wrote:
If I was "placing" Daisy I would call her a Beagle/Lab cross. At least I'd know she'd be adopted. :B

:B We never see Pit crosses coming from rescues around this area. Go figure...

[CA_POPPY]

Coco sure looks like Aussie mixed with BBD (big black dog) to me. Does she have herding instincts? I love mutts, she's beautiful.

[CA_POPPY]

If I was "placing" Daisy I would call her a Beagle/Lab cross. At least I'd know she'd be adopted. :B

[Code2High]

Daisy has no pit in her that I can see... she does look like a pointer mix, but more refined, actually, from that shot. I would believe she had a little sight hound in her before pit. Or brittany, maybe.

It could just be the perspective but the blockhead breeds have a shape to their heads and their snoots that's become quite familiar to me :B It's not there in that face, not at all.

Breed is not necessarily a predictor of prey drive or lack thereof, and my Zig has quite a high prey drive, while the rattie (a breed created for hunting small animals) has pretty much none and would rather eat acorns. There are some increased odds of high prey drive in the hunting breeds, of course, but it's more individual than people realize.

[Sue_Bee]

If I were guessing, from just those pictures, I would say that Daisy is a Greyhound (or some sort of sight hound) mix, based on her legs and head shape, I don't see any sort of pit breed in her, but then, I am not looking at her in 3D, or from all angles.

CoCo, maybe she has standard poodle, I just don't see it though, more likely a mix of some sort of spaniel, perhaps King Charles, with something else. She looks a lot like my one dog, Bear, except Bear is all black. She is also a total spazz, even after going on 4 years, she was 3 when we got her, so she should calm down any time now, and dumb as rocks. I don't have any idea what Bear is, but based on the Spaniels that I have know, she has the spazz and the dumb, the fur, and the drive.

These are the drawbacks with getting any dog where the history is uncertain.

My husband has declared that we aren't ever getting another dog, I say what does he know. Based on our experience, we've always gotten shelter dogs, and have hit on all except the very last one (Bear). The next time, I may just go for a well researched American type field lab, knowing the diseases that labs are prone to.

[Deb_and_Ed_M]

Here's Coco - the "poodle/daschund lapdog" mix who's 60+ lbs and the size of a female GSD

[Deb_and_Ed_M]

Meet Daisy (white w/brown, shorthair) - my daughter Laura's dog. Laura got her from a shelter in Ann Arbor when she was maybe 3 or 4 months old - the shelter swore Daisy's mother was a Sheltie and she'd be a 20-lb "lap dog". Nah - she was a 65-lb dog with tiny feet. She looks like an English Pointer... but had no hunting tendencies; and since they're rather uncommon as a breed, I'm leaning towards pitbull crossed with ? Her dog-aggression issues leaned that way, too....



Notice that Jack (red Cattle Dog) has his eye on Daisy - he STILL has scars on his face from encounters with her.

[Sue_Bee]

Deb and Ed M wrote:
You are right about some backyard breeders just wanting to make a buck, but the same can be said about some rescues and shelters. I've seen firsthand how someone can adopt a pup from a shelter and end up with a dog who's anything but what was described. One of my daughters adopted a "poodle and daschund cross - should mature around 20 lbs" and got a 60 lb Aussie and GSD mix....LOL!!! At least my "designer mutt" won't give me any surprises.

I will concede that there are "shelters" out there that are really "for profit" enterprises disguised as pet rescues, and that "adopting" a pet can be risky, not only that one might not get the dominant breed that one thinks one is getting (I know a woman who brought home a young beagle mix, only he turned out to be a very young treeing coonhound, a much larger dog), but one can be getting a dog with health or behaviour issues as well. However, buying a dog can also be fraught with these same issues when the buyer does not do their homework, whether the dog is a pure breed or designer mutt. Some breeders are using dogs that just should not be breeding, be it for a designer breed, or an AKC registered breed. Just knowing the breed(s) of the puppies does not make for a guarantee of health, temperment, conformation, etc.

dturm wrote:
I often laugh at the breed people assign to puppies. It is very difficult to tell what mixes are included in a puppy under 3-4 months of age. So much easier to see when you monitor body changes as they mature, but it's still a best guess.

Doug, DVM

We have a rescue by us, they used to have most of their medium to large dogs listed as "shepherd mix", "lab mix" or "am staff mix". They have gotten better at identifying breeds now, but it still is often anybody's guess looking at a dog.

[BCSnob]

dturm wrote:
This is where the genetic markers and testing can really benefit because we can get a handle before breeding. But, to be effective breeders have to go through the testing and then breed according to results.

Doug, DVM

I see both extremes in terms of genetic testing; no use of tests and running every available test. Those tests that are relevant for a breed should be run; there is no need to test for a disease where the incident rate in the breed is below 1% (as long as there is no evidence of it in the lines being crossed). Not testing for diseases that are prevalent in the breed is a disservice to the pups, the buyers of the pups, and the entire breed (producing affected pups and adding carriers to the gene pool).

Here is where my point of view differs from most dog owners; most dog owners are concerned about the health of individual dogs where I am concerned about the health of the entire gene pool.

[dturm]

I often laugh at the breed people assign to puppies. It is very difficult to tell what mixes are included in a puppy under 3-4 months of age. So much easier to see when you monitor body changes as they mature, but it's still a best guess.

One problem with genetic problems is that many don't manifest until the dogs are older. Many have gone through multiple breeding cycles, some have already ended their breeding life when the disease/condition appears.

This is where the genetic markers and testing can really benefit because we can get a handle before breeding. But, to be effective breeders have to go through the testing and then breed according to results.

Even without genetic testing and with very apparent problems both medical and behavioral, this isn't always done.

Doug, DVM

[Code2High]

Deb and Ed M wrote:

Sue Bee wrote:
Off topic, somewhat, but it irks me to no end that people go out and spend big money on "designer breed" dogs thinking that they are getting some sort of hybrid vigor, when many of the "breeders" of these dogs are starting with poor breeding stock, since many of these breeders, not all, but a good many of them, are just BYBs with no knowledge of good genetics, and are in it only to make a buck.

A person would be better off either getting a mutt from the city pound, or researching actual accepted pure breeds of dogs and finding a reputable breeder who knows what they are doing.

You are right about some backyard breeders just wanting to make a buck, but the same can be said about some rescues and shelters. I've seen firsthand how someone can adopt a pup from a shelter and end up with a dog who's anything but what was described. One of my daughters adopted a "poodle and daschund cross - should mature around 20 lbs" and got a 60 lb Aussie and GSD mix....LOL!!! At least my "designer mutt" won't give me any surprises.

Rescues and shelters aren't "looking to make a buck," though. They are put in the position of guessing, and yes, that does result in surprises when you adopt a young puppy.

Adopting an older puppy/adolescent/adult dog is another way to avoid that problem.

[Deb_and_Ed_M]

Maybe my willingness to pay for a specific type of mutt harkens back to my "horse days"?? Where it's VERY common to cross-breed, whether for a sport (dressage horses are often crosses); or simply because the end result will be flashy (my sis showed Arab/Pinto crosses for decades). There's a term called Warmblood that refers to any one of several combinations of horse breeds, and they sell for hundreds of thousands of dollars. So yeah - it hardly shocks me to pay a bunch of money for a mutt. Has nothing to do with hybrid vigor and everything to do with desirable qualities.

[Deb_and_Ed_M]

Sue Bee wrote:
Off topic, somewhat, but it irks me to no end that people go out and spend big money on "designer breed" dogs thinking that they are getting some sort of hybrid vigor, when many of the "breeders" of these dogs are starting with poor breeding stock, since many of these breeders, not all, but a good many of them, are just BYBs with no knowledge of good genetics, and are in it only to make a buck.

A person would be better off either getting a mutt from the city pound, or researching actual accepted pure breeds of dogs and finding a reputable breeder who knows what they are doing.

You are right about some backyard breeders just wanting to make a buck, but the same can be said about some rescues and shelters. I've seen firsthand how someone can adopt a pup from a shelter and end up with a dog who's anything but what was described. One of my daughters adopted a "poodle and daschund cross - should mature around 20 lbs" and got a 60 lb Aussie and GSD mix....LOL!!! At least my "designer mutt" won't give me any surprises.